Freestyle Optimum Intake to pump size?

[CARBONX2]

Impeller pitch and nozzle size?

I am running an oem 155 stator and wear ring. I blueprinted the pump a bit but more grinding was actually done to fit my tbm pump stuffer. This gave me a big hub so I got a e-75 skat swirl. Use my superjet drive shaft and rear bearing. I run a skat adj gp1300 reduction nozzle, gp1100 trim ring and an fx140 turn nozzle.

 

[D-Roc]

9/15 with mid size tail cone and 90 mm reduction nozzle ring.

 

[vshockey10]

Do you think the 155 would be as effective with the stock 144 pump tunnel?

 

[CARBONX2]

No, cavitation due to starvation of the pump

 

[D-Roc]

Yup my buddy did 155 in a blaster and 1100 triple. It did have some hookup issues if I remember correctly it was cavitation down low where we need it. If your going to do it, you gotta do it right. I tried to account for everything to make sure that didn't happen with my ski.

 

[geraban19]

Hijacking thread, guys, what about a intake duct for 148mm pump...

Which one to get??? It doesnt make sense to run even 148 with the oem std intake duct.

Gera

 

[D-Roc]

148 with the correct pump shoe is not going to be starving IMO. In a perfect world you could use the volume of the 144 intake that Yamaha engineers designed and create a ratio. Plug in the new pump size to see how much volume you would need to feed the pump. As according to Yamaha.
I feel that my intake is too big for the pitch I am running in my 155 but it is only noticeable at full speed.

 

[geraban19]

D-roc, it is a newer style SJ which seems to have a larger intake area...

My question is about a intake duct. The plastic one looks smaller than 144 and the aluminum looks not larger.

What you recomend??

Thanks

Gera

148 with the correct pump shoe is not going to be starving IMO. In a perfect world you could use the volume of the 144 intake that Yamaha engineers designed and create a ratio. Plug in the new pump size to see how much volume you would need to feed the pump. As according to Yamaha.
I feel that my intake is too big for the pitch I am running in my 155 but it is only noticeable at full speed.

 

[D-Roc]

I think if your plastic or aluminum pump shoe is smaller diameter than whatever size pump you use, there will be starvation issue regardless of the hull intake duct/area size. The aluminum one can at least be bored out to match a 148 and still retain its strength. I have not tried to open up a plastic pump shoe, I imagine it would be very weak.

 

[Matt_E]

I think if your plastic or aluminum pump shoe is smaller diameter than whatever size pump you use, there will be starvation issue regardless of the hull intake duct/area size. The aluminum one can at least be bored out to match a 148 and still retain its strength. I have not tried to open up a plastic pump shoe, I imagine it would be very weak.

You can do it with an OEM shoe, but it is skeletonized so you have to fill the voids with JB weld beforehand.